Sleep-related breathing disorders in infants with spina bifida repaired prenatally and postnatally

STUDY OBJECTIVES

Advances in prenatal repair of myelomeningocele (MMC) have improved outcomes involving different organ systems. There is limited data on respiratory outcomes following prenatal surgical repair. We hypothesize there is no difference in respiratory outcomes between spina bifida (SB) patients who have undergone prenatal versus postnatal repair.

METHODS

We performed a retrospective study of 46 infants <1 year with SB seen at Children's Hospital Los Angeles from 2004-2022. Demographic data, timing of closure, neonatal course, Chiari II malformation (CIIM), ventriculoperitoneal shunt (VPS), polysomnography (PSG) results, and need for supplemental oxygen were collected. Unpaired t-test and Chi-square Test were used to analyze results.

RESULTS

31/46 had prenatal repair of MMC; average age at repair was 27 weeks post-conception (PCA). Average age at postnatal repair was 37 PCA. There was no difference in age at PSG. There was no difference in CIIM presence (p=0.61). 60% of patients with postnatal repair and 23% in the prenatal group underwent VPS placement (p=0.01).

There was no difference in PSG findings between the two groups: CAI (p=0.11), OAHI (p=0.64), average SpO2 baseline (p=0.91), average SpO2 nadir (p=0.17), average PETCO2 baseline (p=0.87), and average PETCO2 maximum (p=0.54). There were no significant differences in the proportion of patients on supplemental O2 (p=0.25), CSA or OSA between groups.

CONCLUSIONS

Patients with SB who've undergone closure of neural tube defect have persistent central apneas, obstructive apneas, and significant hypoxemia. There were no differences in the frequency or severity of sleep-disordered breathing in those with prenatal repair versus postnatal repair.

Closing the gap between science and management of cold-water refuges in rivers and streams

Human activities and climate change threaten coldwater organisms in freshwater ecosystems by causing rivers and streams to warm, increasing the intensity and frequency of warm temperature events, and reducing thermal heterogeneity. Cold-water refuges are discrete patches of relatively cool water that are used by coldwater organisms for thermal relief and short-term survival. Globally, cohesive management approaches are needed that consider interlinked physical, biological, and social factors of cold-water refuges. We review current understanding of cold-water refuges, identify gaps between science and management, and evaluate policies aimed at protecting thermally sensitive species. Existing policies include designating cold-water habitats, restricting fishing during warm periods, and implementing threshold temperature standards or guidelines. However, these policies are rare and uncoordinated across spatial scales and often do not consider input from Indigenous peoples. We propose that cold-water refuges be managed as distinct operational landscape units, which provide a social and ecological context that is relevant at the watershed scale. These operational landscape units provide the foundation for an integrated framework that links science and management by (1) mapping and characterizing cold-water refuges to prioritize management and conservation actions, (2) leveraging existing and new policies, (3) improving coordination across jurisdictions, and (4) implementing adaptive management practices across scales. Our findings show that while there are many opportunities for scientific advancement, the current state of the sciences is sufficient to inform policy and management. Our proposed framework provides a path forward for managing and protecting cold-water refuges using existing and new policies to protect coldwater organisms in the face of global change.

Using a mobile health app in a weight management program for overweight and obese adolescents and young adults with spina bifida

CONTEXT

Adolescents and young adults (AYA) with spina bifida (SB) are more susceptible to obesity due to impaired mobility. There is limited access to physical activity for this population.

OBJECTIVE

The primary aim of this study was to evaluate the feasibility of a mobile health app in a weight management program for AYA with SB. This was determined by measuring program adherence, active use of the app (defined as ≥3 uses per week), and user rating of the Pt Pal™ mobile app. Secondary outcomes were changes in BMI, quality of life, and health behavior, and the number of active participants over time.

METHODS

Patients from the SB Clinic of a large metropolitan hospital between the ages of 11-21 years and overweight were invited to participate. The program consisted of group nutrition sessions and an individualized exercise plan using a mobile app with coaching. Outcome measures were program adherence, changes in BMI, and validated survey responses. Descriptive statistical analysis was performed.

RESULTS

Fifteen participants enrolled, and ten participants completed the program. Five of the ten participants attended the nutrition sessions. The number of active app users declined after the first week. Seventy percent of participants decreased their BMI. Most participants reported the program improved their ability to exercise regularly, eat a healthier diet and feel more self-confident. Peds QL™ psychosocial health domains increased postintervention. The YRBS showed increased physical activity and less sedentary time postintervention.

CONCLUSIONS

This mobile app-based weight management program with coaching implemented may not be feasible for adoption in the general population of AYA with SB; however, it was well received by some, and further testing is needed to determine how to improve feasibility. This study provides useful information to guide future programs utilizing digital health and coaching.

Education and employment as young adults living with spina bifida transition to adulthood in the USA: A study of the National Spina Bifida Patient Registry

AIM

To describe the education and employment transition experience of young adults with spina bifida (YASB) and investigate factors associated with employment.

METHOD

We queried education and employment data from the US National Spina Bifida Patient Registry from 2009 to 2019. We applied generalized estimating equations models to analyze sociodemographic and disease-related factors associated with employment.

RESULTS

A total of 1909 participants (850 males, 1059 females) aged 18 to 26 years contributed 4379 annual visits. Nearly 84% had myelomeningocele and, at last visit, the median age was 21 years (mean 21 years 5 months, SD 2 years 10 months). A total of 41.8% had at least some post-high school education, and 23.9% were employed. In a multivariable regression model, employment was significantly associated with education level, lower extremity functional level, bowel continence, insurance, and history of non-shunt surgery. This large, national sample of YASB demonstrated low rates of post-secondary education attainment and employment and several potentially modifiable factors associated with employment.

INTERPRETATION

Specific sociodemographic, medical, and functional factors associated with employment are important for clinicians to consider when facilitating transition for YASB into adulthood. Additional research is needed to understand the impact of cognitive functioning and social determinants of health on transition success in YASB.

WHAT THIS PAPER ADDS

There were low education attainment and employment rates in a large sample of young adults with spina bifida. Specific sociodemographic, medical, and functional factors are associated with employment. Some employment-associated factors, such as continence and self-management skills, are modifiable.

Risk factors for unanticipated hospitalizations in children and youth with spina bifida at an urban children's hospital: A cross-sectional study

BACKGROUND

Spina bifida (SB) is a condition resulting from the improper closure of the neural tube and vertebral column during fetal development. While patients' life expectancy and quality of life have improved dramatically due to medical advances, children continue to experience health-related issues that often require hospitalizations.

OBJECTIVE

The association among sociodemographic and clinical characteristics with potentially preventable hospitalizations (PPH) in children and youth with myelomeningocele type SB was investigated in this cross-sectional study.

METHODS

Chart reviews and data extraction were conducted on 108 children and youth, ages 1 month to 21 years, admitted for PPH in a regional children's academic medical center between May 2017 and July 2019. Sociodemographic variables included sex, age, type of insurance and ethnicity. Clinical variables included level of lesion, ambulation status, shunt dependency and selected diagnostic categories. Univariate, bivariate, and multivariate analyses were conducted to identify factors associated with PPH.

RESULTS

Factors associated with PPH included being male, ages 5-18 years, low lumbar level lesions, non-ambulatory, with public insurance, Hispanic and shunt dependent. Most hospitalizations (73%) were for neurologic or urologic conditions. Factors independently associated with PPH were ethnicity for urologic conditions, being ambulatory for metabolic conditions, and age for gastroenterology conditions.

CONCLUSION

Selected demographic and clinical variables were found to be associated with PPH of children and youth with myelomeningocele-type SB. The most common reasons for PPH were shunt malfunctions and urinary tract infections, consistent with other studies.

Plant peroxisome proteostasis-establishing, renovating, and dismantling the peroxisomal proteome

Plant peroxisomes host critical metabolic reactions and insulate the rest of the cell from reactive byproducts. The specialization of peroxisomal reactions is rooted in how the organelle modulates its proteome to be suitable for the tissue, environment, and developmental stage of the organism. The story of plant peroxisomal proteostasis begins with transcriptional regulation of peroxisomal protein genes and the synthesis, trafficking, import, and folding of peroxisomal proteins. The saga continues with assembly and disaggregation by chaperones and degradation via proteases or the proteasome. The story concludes with organelle recycling via autophagy. Some of these processes as well as the proteins that facilitate them are peroxisome-specific, while others are shared among organelles. Our understanding of translational regulation of plant peroxisomal protein transcripts and proteins necessary for pexophagy remain based in findings from other models. Recent strides to elucidate transcriptional control, membrane dynamics, protein trafficking, and conditions that induce peroxisome turnover have expanded our knowledge of plant peroxisomal proteostasis. Here we review our current understanding of the processes and proteins necessary for plant peroxisome proteostasis-the emergence, maintenance, and clearance of the peroxisomal proteome.

Image guidance system use amongst Canadian otolaryngologists: a nationwide survey

Background

The use of image guidance systems has gained widespread acceptance as an adjunctive tool for endoscopic sinus surgery. However, the accessibility and usage of this technology is variable across hospitals in Canada.

Study objective

The aim of this study is to investigate the availability, usage, and related issues surrounding the use of image guidance systems in endoscopic sinus surgery across Canadian otolaryngology practice settings.

Methods

An online survey was electronically distributed to practicing otolaryngologists across Canada. The survey contained 27 questions pertaining to the availability, usage, barriers and overall experience of image guidance systems.

Results

The survey was electronically sent to a total of 654 Canadian otolaryngologists of which 158 responded (response rate 24.2%). Image guidance was available to 56.3% of respondents. Of the respondents without access to IGS, 85.5% indicated they would use it if it was available. Financial (capital cost) was identified as the most important barrier in obtaining IGS by 76.3% of respondents.

Conclusion

Over half of Canadian otolaryngologists have access to IGS with over 85% of those without access interested in using it if it was made available. A multitude of different factors contribute to this disparity. We hope that the results of this study will help support Canadian otolaryngologists to access IGS.

Graphical Abstract

Exploratory study of the provision of academic and health-related accommodations to transition-age adolescents and emerging adults with spina bifida

PURPOSE

The purpose of this exploratory study was to investigate the types of academic and health-related accommodations provided to adolescents and emerging adults with spina bifida aged 9-20 years.

METHODS

Data were extracted from the paper and electronic records of transition-age youth enrolled in the study. Four open ended items involved content analysis.

RESULTS

The most frequently identified accommodation was enrollment in special education classes in 47.7% of the charts. Other academic accommodations that were most often reported were adaptive physical education (n = 71, 39.9%), tutoring (n = 28; 15.7%), and home schooling (n = 21; 11.8%). Clean intermittent catheterization was the most frequently identified health-related accommodation provided by the school nurse/aide (n = 57; 32%).The largest percentage of requests for additional accommodations were made during the middle school grades (15; 54.8%) followed by high school (10; 32.2%).

CONCLUSION

Findings demonstrated that persistent issues were identified by parents/adolescents regarding the provision of school-related accommodations. This is a relevant area for clinical practice to ensure students with special health care needs and those with spina bifida receive the academic and health-related accommodations in their Individualized Education Program/504 plans.

Improved pyrrolysine biosynthesis through phage assisted non-continuous directed evolution of the complete pathway

Pyrrolysine (Pyl, O) exists in nature as the 22^nd proteinogenic amino acid. Despite being a fundamental building block of proteins, studies of Pyl have been hindered by the difficulty and inefficiency of both its chemical and biological syntheses. Here, we improve Pyl biosynthesis via rational engineering and directed evolution of the entire biosynthetic pathway. To accommodate toxicity of Pyl biosynthetic genes in Escherichia coli, we also develop Alternating Phage Assisted Non-Continuous Evolution (Alt-PANCE) that alternates mutagenic and selective phage growths. The evolved pathway provides 32-fold improved yield of Pyl-containing reporter protein compared to the rationally engineered ancestor. Evolved PylB mutants are present at up to 4.5-fold elevated levels inside cells, and show up to 2.2-fold increased protease resistance. This study demonstrates that Alt-PANCE provides a general approach for evolving proteins exhibiting toxic side effects, and further provides an improved pathway capable of producing substantially greater quantities of Pyl-proteins in E. coli.

Pyrrolysine (Pyl) exists in nature as the 22^nd proteinogenic amino acid, but studies of Pyl have been hindered by the difficulty and inefficiency of both its chemical and biological syntheses. Here, the authors developed an improved PANCE approach to evolve the pylBCD pathway for increased production of Pyl proteins in E. coli.

CSO (Canadian Society of Otolaryngology - Head & Neck Surgery) position paper on return to Otolaryngology - Head & Neck Surgery Clinic Practice during the COVID-19 pandemic in Canada

The novel Coronavirus (COVID-19) has created a worldwide deadly pandemic that has become a major public health challenge. All semi-urgent and elective medical care has come to a halt to conserve capacity to care for patients during this pandemic. As the numbers of COVID-19 cases decrease across Canada, our healthcare system also began to reopen various facilities and medical offices. The aim for this document is to compile the current evidence and provide expert consensus on the safe return to clinic practice in Otolaryngology - Head & Neck Surgery. These recommendations will also summarize general precaution principles and practical tips for office across Canada to optimize patient and provider safety. Risk assessment and patient selection are crucial to minimizing exposure to COVID-19. Controversial topics such as COVID-19 mode of transmission, duration of exposure, personal protective equipment, and aerosol-generating procedures will be analyzed and discussed. Practical solutions of pre-visit office preparation, front office and examination room set-up, and check out procedures are explored. Specific considerations for audiology, pediatric population, and high risk AGMPs are also addressed. Given that the literature surrounding COVID-19 is rapidly evolving, these guidelines will serve to start our specialty back into practice over the next weeks to months and they may change as we learn more about this disease.

Racial and Ethnic Differences in Behavioral Problems and Medication Use Among Children With Autism Spectrum Disorders

We examined racial and ethnic differences in the prevalence of behavioral problems measured by the Child Behavioral Checklist (CBCL), sleep disturbances measured by the Child Sleep Habits Questionnaire (CSHQ), and medication use among children with Autism Spectrum Disorders (ASD). We analyzed data from the Autism Treatment Network (ATN) dataset for 2,576 children ages 6 to 18 years of age diagnosed with ASD. Multivariable logistic regression accounting for age, gender, Diagnostic and Statistical Manual of Mental Disorders (4th Edition - Text Revision), diagnosis (Autistic Disorder, PDD-NOS, Asperger's Disorder), and parents' education did not show any racial or ethnic differences in behavioral challenges, conduct problems, or sleep disturbances for any of the groups, but Black children had lower odds of Total Problem Behaviors and Asian children had lower odds of Hyperactivity compared to White children. As a group, children from racial and ethnic minorities had lower odds of Total Problem Behaviors and Conduct Problems compared to White children. Hispanic children had lower odds of medication use for Behavioral Challenges, Total Problem Behaviors, Hyperactivity, and Conduct Problems. Asian children had lower odds of medication use for Behavioral Challenges, Total Problem Behaviors, and Hyperactivity; and had close to lower odds in medication use for Conduct Problems. Black children had lower odds for medication use for Total Problem Behaviors only. As a group, children from racial and ethnic minorities had lower odds for medication use for Behavioral Challenges, Total Problem Behaviors, Hyperactivity, and Conduct problems, but not for Sleep Disturbances. While these results are consistent with previous studies showing that White children are significantly more likely to receive psychotropic medication compared to children from racial and ethnic minority groups, we found no such differences for sleep challenges, suggesting that they are more consistently identified and equitably treated than other behavioral problems associated with ASD. We draw upon Andersen's (1995) Behavioral Model of Healthcare Use to suggest predisposing, enabling, and needs factors that may contribute to this pattern of racial and ethnic differences in the use of medications among children ASD.

Deciphering the Role of Colicins during Colonization of the Mammalian Gut by Commensal E. coli

Colicins are specific and potent toxins produced by Enterobacteriaceae that result in the rapid elimination of sensitive cells. Colicin production is commonly found throughout microbial populations, suggesting its potential importance for bacterial survival in complex microbial environments. Nonetheless, as colicin biology has been predominately studied using synthetic models, it remains unclear how colicin production contributes to survival and fitness of a colicin-producing commensal strain in a natural environment. To address this gap, we took advantage of MP1, an E. coli strain that harbors a colicinogenic plasmid and is a natural colonizer of the murine gut. Using this model, we validated that MP1 is competent for colicin production and then directly interrogated the importance of colicin production and immunity for MP1 survival in the murine gut. We showed that colicin production is dispensable for sustained colonization in the unperturbed gut. A strain lacking colicin production or immunity shows minimal fitness defects and can resist displacement by colicin producers. This report extends our understanding of the role that colicin production may play for E. coli during gut colonization and suggests that colicin production is not essential for a commensal to persist in its physiologic niche in the absence of exogenous challenges.

Philosophy of care delivery for spina bifida

The multidisciplinary model (MCM) is described as one that utilizes skills and experience from practitioners belonging to various disciplines, each treating patients from a specific clinical perspective.1 The Spina Bifida Association (SBA) supports and recommends that clinical care for people with Spina Bifida (SB) be provided in specialty clinics of which the MCM is an example; that care be coordinated; and that there be a plan for transitional care.2 This paper explores the challenges the MCM faces with a transitioning and aging population in a care system that calls for a positive patient experience, engaged health care professionals, desired outcomes, with consideration of cost.

Disparities in Service Use Among Children With Autism: A Systematic Review

CONTEXT

Research reveals racial, ethnic, and socioeconomic disparities in autism diagnosis; there is limited information on potential disparities related to other dimensions of services.

OBJECTIVE

We reviewed evidence related to disparities in service use, intervention effectiveness, and quality of care provided to children with autism by race, ethnicity, and/or socioeconomic status.

DATA SOURCES

Medline, PsychInfo, Educational Resources Informational Clearinghouse, and the Cumulative Index to Nursing and Allied Health Literature were searched by using a combination of Medical Subject Headings terms and keywords related to autism, disparities, treatment, and services.

STUDY SELECTION

Included studies addressed at least one key question and met eligibility criteria.

DATA EXTRACTION

Two authors reviewed the titles and abstracts of articles and reviewed the full text of potentially relevant articles. Authors extracted information from articles that were deemed appropriate.

RESULTS

Treatment disparities exist for access to care, referral frequency, number of service hours, and proportion of unmet service needs. Evidence revealed that racial and ethnic minority groups and children from low-income families have less access to acute care, specialized services, educational services, and community services compared with higher-income and white families. We found no studies in which differences in intervention effectiveness were examined. Several studies revealed disparities such that African American and Hispanic families and those from low-income households reported lower quality of care.

LIMITATIONS

The body of literature on this topic is small; hence it served as a limitation to this review.

CONCLUSIONS

The documented disparities in access and quality of care may further identify groups in need of outreach, care coordination, and/or other interventions.

Performance of Standardized Relative CBV for Quantifying Regional Histologic Tumor Burden in Recurrent High-Grade Glioma: Comparison against Normalized Relative CBV Using Image-Localized Stereotactic Biopsies

BACKGROUND AND PURPOSE

Perfusion MR imaging measures of relative CBV can distinguish recurrent tumor from posttreatment radiation effects in high-grade gliomas. Currently, relative CBV measurement requires normalization based on user-defined reference tissues. A recently proposed method of relative CBV standardization eliminates the need for user input. This study compares the predictive performance of relative CBV standardization against relative CBV normalization for quantifying recurrent tumor burden in high-grade gliomas relative to posttreatment radiation effects.

MATERIALS AND METHODS

We recruited 38 previously treated patients with high-grade gliomas (World Health Organization grades III or IV) undergoing surgical re-resection for new contrast-enhancing lesions concerning for recurrent tumor versus posttreatment radiation effects. We recovered 112 image-localized biopsies and quantified the percentage of histologic tumor content versus posttreatment radiation effects for each sample. We measured spatially matched normalized and standardized relative CBV metrics (mean, median) and fractional tumor burden for each biopsy. We compared relative CBV performance to predict tumor content, including the Pearson correlation (r), against histologic tumor content (0%-100%) and the receiver operating characteristic area under the curve for predicting high-versus-low tumor content using binary histologic cutoffs (≥50%; ≥80% tumor).

RESULTS

Across relative CBV metrics, fractional tumor burden showed the highest correlations with tumor content (0%-100%) for normalized (r = 0.63, P < .001) and standardized (r = 0.66, P < .001) values. With binary cutoffs (ie, ≥50%; ≥80% tumor), predictive accuracies were similar for both standardized and normalized metrics and across relative CBV metrics. Median relative CBV achieved the highest area under the curve (normalized = 0.87, standardized = 0.86) for predicting ≥50% tumor, while fractional tumor burden achieved the highest area under the curve (normalized = 0.77, standardized = 0.80) for predicting ≥80% tumor.

CONCLUSIONS

Standardization of relative CBV achieves similar performance compared with normalized relative CBV and offers an important step toward workflow optimization and consensus methodology.

Nitrogen use efficiency and nitrous oxide emissions from five UK fertilised grasslands

Intensification of grasslands is necessary to meet the increasing demand of livestock products. The application of nitrogen (N) on grasslands affects the N balance therefore the nitrogen use efficiency (NUE). Emissions of nitrous oxide (N₂O) are produced due to N fertilisation and low NUE. These emissions depend on the type and rates of N applied. In this study we have compiled data from 5 UK N fertilised grassland sites (Crichton, Drayton, North Wyke, Hillsborough and Pwllpeiran) covering a range of soil types and climates. The experiments evaluated the effect of increasing rates of inorganic N fertiliser provided as ammonium nitrate (AN) or calcium ammonium nitrate (CAN). The following fertiliser strategies were also explored for a rate of 320 kg N ha^-1: using the nitrification inhibitor dicyandiamide (DCD), changing to urea as an N source and splitting fertiliser applications. We measured N₂O emissions for a full year in each experiment, as well as soil mineral N, climate data, pasture yield and N offtake. N₂O emissions were greater at Crichton and North Wyke whereas Drayton, Hillsborough and Pwllpeiran had the smallest emissions. The resulting average emission factor (EF) of 1.12% total N applied showed a range of values for all the sites between 0.6 and 2.08%. NUE depended on the site and for an application rate of 320 kg N ha^-1, N surplus was on average higher than 80 kg N ha^-1, which is proposed as a maximum by the EU Nitrogen Expert Panel. N₂O emissions tended to be lower when urea was applied instead of AN or CAN, and were particularly reduced when using urea with DCD. Finally, correlations between the factors studied showed that total N input was related to Nofftake and Nexcess; while cumulative emissions and EF were related to yield scaled emissions.

Accurate Patient-Specific Machine Learning Models of Glioblastoma Invasion Using Transfer Learning

BACKGROUND AND PURPOSE

MR imaging-based modeling of tumor cell density can substantially improve targeted treatment of glioblastoma. Unfortunately, interpatient variability limits the predictive ability of many modeling approaches. We present a transfer learning method that generates individualized patient models, grounded in the wealth of population data, while also detecting and adjusting for interpatient variabilities based on each patient's own histologic data.

MATERIALS AND METHODS

We recruited patients with primary glioblastoma undergoing image-guided biopsies and preoperative imaging, including contrast-enhanced MR imaging, dynamic susceptibility contrast MR imaging, and diffusion tensor imaging. We calculated relative cerebral blood volume from DSC-MR imaging and mean diffusivity and fractional anisotropy from DTI. Following image coregistration, we assessed tumor cell density for each biopsy and identified corresponding localized MR imaging measurements. We then explored a range of univariate and multivariate predictive models of tumor cell density based on MR imaging measurements in a generalized one-model-fits-all approach. We then implemented both univariate and multivariate individualized transfer learning predictive models, which harness the available population-level data but allow individual variability in their predictions. Finally, we compared Pearson correlation coefficients and mean absolute error between the individualized transfer learning and generalized one-model-fits-all models.

RESULTS

Tumor cell density significantly correlated with relative CBV (r = 0.33, P < .001), and T1-weighted postcontrast (r = 0.36, P < .001) on univariate analysis after correcting for multiple comparisons. With single-variable modeling (using relative CBV), transfer learning increased predictive performance (r = 0.53, mean absolute error = 15.19%) compared with one-model-fits-all (r = 0.27, mean absolute error = 17.79%). With multivariate modeling, transfer learning further improved performance (r = 0.88, mean absolute error = 5.66%) compared with one-model-fits-all (r = 0.39, mean absolute error = 16.55%).

CONCLUSIONS

Transfer learning significantly improves predictive modeling performance for quantifying tumor cell density in glioblastoma.

An exploratory study of adolescents and emerging adults with spina bifida knowledge of their individual education program: Implications for health care transition planning

PURPOSE

The purpose of this study was to explore adolescents and emerging adults (AEA) with spina bifida (SB) understanding of their Individualized Education Program (IEP) and to identify factors related to their knowledge about their own IEP.

METHODS

Data were collected from January 2015 to July 2016 from 79 adolescents with SB. A ten-item questionnaire including demographics and questions specifically addressing IEPs was used. Qualitative analysis followed an iterative, emergent approach. Two experienced coders independently read and coded each of the three open-ended questions. It was determined that the responses of all three questions could feasibly be merged as the analysis of responses were similar.

FINDINGS

This was a predominately 70 (88.7%) Hispanic sample of AEA with SB who ranged in age from 12 to 20 years (M= 15.3 years) consisting of 41 males and 38 females. All reported they have/had an IEP. Four major themes and eleven subthemes emerged from the analysis. Major themes were: The Barometer of How I Am Doing, Creating the Right Match for Learning, Obtaining the Assistance I Need, and Future Goals and Planning.

CONCLUSIONS

Findings of this study reveal the IEP knowledge gaps and lack of lifestyle self-management skills AEA with SB reported pertaining to IEPs.

Differences in continence rates in individuals with spina bifida based on ethnicity

BACKGROUND

Ethnic disparities in continence rates in spina bifida (SB) have been studied regionally but not nationally. National SB Patient Registry (NSBPR) data were analyzed to explore differences in prevalence of bowel and bladder continence and interventions between Hispanics/Latinos and others.

METHODS

Participants 5 to 21 years were categorized into Hispanic/Latino and non-Hispanic/non-Latino. Bladder/bowel continence was defined as dry/no involuntary stool leakage during the day or none/⩽ monthly incontinence. Chi-square test, Wilcoxon Two Sample Test, and generalized estimating equation (GEE) were used for statistical analysis.

RESULTS

Twenty-five percent of the 4,364 patients were Hispanic/Latino. At their most recent clinic visit, Hispanics/Latinos demonstrated lower rates of urinary continence (38.6% vs. 44.9%; p= 0.0003), bowel continence (43.9% vs. 55.8%, p< 0.0001), private insurance (p< 0.0001), bowel (p< 0.0001) or bladder surgeries (p= 0.0054), and more vesicostomies (p= 0.0427) compared to others. In multiple GEE models, Hispanic/Latino participants demonstrated lower odds of bowel continence as compared to non-Hispanic/non-Latino participants (estimated odds ratio, 0.82, 95% CI, 0.72-0.94, p= 0.0032).

CONCLUSIONS

After controlling for covariates, Hispanics/Latinos with SB are less likely to report bowel continence. Clinicians are encouraged to consider the risk of negative health disparities for Hispanic patients with SB and work to mitigate this risk.

Selecting a Structural Analog as an Internal Standard for the Quantification of 6-Methylmercaptopurine by LC-MS/MS

BACKGROUND

When choosing an analog internal standard (IS) in a quantitative LC-MS/MS assay, careful selection and thorough verification are important for developing an accurate quantitative assay. The IS is a critical component in quantitative mass spectrometry because it is used to normalize results by compensating for variations in sample preparation and instrument performance. Here we present the results of our investigation in the selection process for a structural analog IS (SA-IS) to be used in the quantification of 6-methylmercaptopurine (6-MMP) in cytolysed red blood cell (RBC).

METHODS

A cocktail solution of 9 SA-ISs including the isotopically labeled structural isomer and the 6-MMP stable isotope-labeled IS (SIL-IS) was spiked into cytolysed RBC controls and patient samples. Linearity, accuracy, sensitivity, precision, run stability, method comparison, and reinjection reproducibility experiments were performed. Ion suppression was also assessed by T-infusing the cocktail solution.

RESULTS

All analogs were linear from 100 to 1200 ng/mL 6-MMP with acceptable precision and sensitivity by use of a spiked blank lysate. Method comparison plots of 6-MMP concentrations in patient samples had excellent agreement for 2 of the SA-ISs (i.e., the isotopically labeled structural isomer and an SA-IS with an added methyl group) when compared to the SIL-IS. Halogen-substituted analogs (i.e., Cl and Br) also met the criteria as an acceptable IS. However, 2 of the selected SA-ISs having substituted amine moieties showed unacceptable performance, with ≥15% bias when compared to the SIL-IS.

CONCLUSION

There are many parameters to consider when determining if an analog will be a good IS choice, and the approaches highlighted in this article can be applied to the selection of SA-IS in the development of other LC-MS/MS assays.

Tick infestations of wildlife and companion animals in Ontario, Canada, with detection of human pathogens in Ixodes scapularis ticks

The growing risk of transmission of tick-borne zoonotic pathogens to humans in Ontario, Canada, warrants investigations into regional tick distribution, tick burdens of local peridomestic animals, and prevalence of tick-borne pathogens. The objectives of this study were to investigate the geographic distribution and magnitude of tick infestations in opportunistically sampled mammalian wildlife and companion animals (i.e., dogs) in southern Ontario and to test these ticks for evidence of zoonotic tick-borne pathogens. Ticks collected from wildlife carcasses, live-trapped wildlife and companion animals (2015-2016), as well as wildlife diagnostic cases (2011-2013), were identified to species and life stage. Ixodes scapularis ticks were tested by real-time PCR for Anaplasma phagocytophilum, Babesia microti, Borrelia miyamotoi and Borrelia burgdorferi sensu stricto (s.s.). Amblyomma americanum ticks were tested for Ehrlichia chaffeensis. A total of 1687 ticks of six species were collected from 334 animals, including 224 raccoons (n = 1381 ticks) and 50 dogs (n = 67 ticks). The most common tick species collected from parasitized raccoons were Ixodes texanus (n = 666 ticks) and Dermacentor variabilis (n = 600 ticks), which were removed from 58.5% (median: 2 ticks; range: 1-36) and 49.1% (median: 2 ticks; range: 1-64) of raccoons, respectively. Of I. scapularis tested, 9.3% (4/43) were positive for Bo. burgdorferi s.s. and 2.3% (1/43) for A. phagocytophilum. These results reveal that numerous tick species parasitize common, peridomestic wildlife and that at least two zoonotic, tick-borne pathogens circulate in southern Ontario. Host-tick vector-pathogen dynamics should continue to be monitored in the face of global climate change, landscape alterations and expanding human populations.

Maternal beliefs about autism: A link between intervention services and autism severity in White and Latino mothers

Variation in parental beliefs about Autism Spectrum Disorder (ASD) may impact subsequent service use profiles. This study aimed to examine (1) variation in beliefs about ASD among English language proficient White (EP-W) mothers, English language proficient Latino (EPL) mothers, and limited English language proficient Latino (LEP-L) mothers of children with ASD; (2) variation in beliefs about ASD in the context of the child's ASD severity, among EP White mothers, EP Latino others, and LEP Latino mothers; and (3) potential links between maternal beliefs about ASD and children's current ASD treatment. This multi-site study included 305 English or Spanish-speaking parents of children with ASD, ages 2-10 years, who completed a survey about their beliefs about their child's ASD, their child's ASD severity, and treatments used by their children. Results showed that mothers in the EP-W, EP-L, and LEP-L groups differed in their beliefs about viewing ASD as a mystery. Only maternal views of ASD severity in the EP-W group were linked to their beliefs about ASD. Finally, maternal beliefs about ASD having major consequences on their child's life, and ASD being a mystery were strongly associated with a child's use of ASD intervention services. These findings provide new knowledge of how maternal beliefs about ASD vary in linguistically diverse groups, how a child's ASD severity may influence such beliefs, and how maternal beliefs correlate with the amount of therapy children with ASD receive. Future research should address how these beliefs or views are formed, what factors influence them, or whether they are malleable. Understanding parents' beliefs or views of having a child with ASD can potentially help us increase use of ASD intervention services in families of children with ASD.

Design and Methodological Considerations of the Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida

PURPOSE

Care of children with spina bifida has significantly advanced in the last half century, resulting in gains in longevity and quality of life for affected children and caregivers. Bladder dysfunction is the norm in patients with spina bifida and may result in infection, renal scarring and chronic kidney disease. However, the optimal urological management for spina bifida related bladder dysfunction is unknown.

MATERIALS AND METHODS

In 2012 the Centers for Disease Control and Prevention convened a working group composed of pediatric urologists, nephrologists, epidemiologists, methodologists, community advocates and Centers for Disease Control and Prevention personnel to develop a protocol to optimize urological care of children with spina bifida from the newborn period through age 5 years.

RESULTS

An iterative quality improvement protocol was selected. In this model participating institutions agree to prospectively treat all newborns with spina bifida using a single consensus based protocol. During the 5-year study period outcomes will be routinely assessed and the protocol adjusted as needed to optimize patient and process outcomes. Primary study outcomes include urinary tract infections, renal scarring, renal function and bladder characteristics. The protocol specifies the timing and use of testing (eg ultrasonography, urodynamics) and interventions (eg intermittent catheterization, prophylactic antibiotics, antimuscarinic medications). Starting in 2014 the Centers for Disease Control and Prevention began funding 9 study sites to implement and evaluate the protocol.

CONCLUSIONS

The Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida began accruing patients in 2015. Assessment in the first 5 years will focus on urinary tract infections, renal function, renal scarring and clinical process improvements.

Evaluation of increasing levels of a microbial phytase in phosphorus deficient broiler diets via live broiler performance, tibia bone ash, apparent metabolizable energy, and amino acid digestibility

The objective was to investigate increasing concentrations of an evolved microbial phytase on male broiler performance, tibia bone ash, AME, and amino acid digestibility when fed diets deficient in available phosphorus (aP). Experiment 1 evaluated the effects of phytase during a 21 d battery cage study and Experiment 2 was a 42 d grow-out. Experiment 1 included six treatments; negative control (NC) with an aP level of 0.23% (starter) and 0.19% (grower), two positive controls (PC) consisting of an additional 0.12% and 0.22% aP (PC 1 and PC 2), and the NC supplemented with three levels of phytase (250, 500, and 2,000 U/kg). The NC diet reduced (P < 0.05) FC, BW, and bone ash. Phytase increased (P < 0.05) BW with 2,000 U/kg phytase yielding similar results to the PC2, and improved FCR and increased bone ash was observed at all phytase levels. Amino acid digestibility coefficients were increased (P < 0.05) with phytase at 250 U/kg. Phytase at all rates increased (P < 0.05) AME to levels similar level as PC diets. Linear regression analysis indicated average P equivalency values for BW and bone ash of 0.137, 0.147, and 0.226 for phytase inclusion of 250, 500, and 2000 U/kg, respectively. Experiment 2 included a PC consisting of 0.45%, 0.41%, and 0.38% aP for the starter, grower, and finisher, respectively; NC with reduced aP of 0.17%; and phytase at 500 and 2,000 U/kg. Phytase increased BW (P < 0.05) compared to the NC as 2,000 U/kg phytase resulted in further BW increases compared to the PC (starter and grower). Phytase improved FCR to levels comparable to the PC, with supplementation at 2,000 U/kg resulting in improvements beyond the PC in the starter phase. Amino acid digestibility coefficients were increased with phytase at 2,000 U/kg to levels comparable to that of the PC. These data confirm that the inclusion of phytase improves broiler performance and bone mineralization in aP reduced diets and levels beyond the traditional 500 U/kg can result in further improvements.

Movin' On Up: An Innovative Nurse-Led Interdisciplinary Health Care Transition Program

This article provides an overview of an innovative nurse-led interdisciplinary health care transition (HCT) model of care entitled Movin' On Up for adolescents and emerging adults (AEAs) with spina bifida (SB) that was originally implemented in 2011. The components of the HCT service model include an HCT nursing specialist, who is an advanced practice nurse; interdisciplinary health care transition plans based on the individualized needs of AEAs; an interdisciplinary HCT team that meets on a weekly basis; direct HCT services provided in the weekly SB clinic; and telephonic follow-up with AEAs, families, and providers. The characteristics of this nurse-led HCT program can be described as an integrated, interdisciplinary, and comprehensive model of care based on a life span approach. To date, a total of 210 AEAs with SB, ages 10 to 20 years, have been enrolled into the program. An important feature of this HCT service model is that it is self-supporting; it generates the revenue needed for sustainability and, unlike other HCT programs, is not reliant on extramural programmatic support. Other accomplishments of Movin' On Up include the development of a transfer protocol wherein 35 AEAs with SB have been supported in their transfer to adult care; implementation of a standardized process to ensure that service referrals to community-based services for postsecondary education, employment, training, and initiation of conservatorships are made; timely performance of evaluations; close tracking of needs and outcomes of self-management knowledge and skills instruction; and attention to equipment needs prior to transfer.

Endoscopic polypectomy in the clinic: a pilot cost-effectiveness analysis

OBJECTIVE

The purpose of this pilot economic evaluation was to assess the cost-effectiveness of the endoscopic polypectomy in the clinic (EPIC) procedure compared to formal endoscopic sinus surgery (ESS) for the treatment of select chronic rhinosinusitis (CRS) patients with nasal polyposis.

DESIGN

Cost-effectiveness analysis using a Markov decision tree model with a 30-year time horizon. The two comparative treatment groups were as follows: (i) EPIC and (ii) ESS. Costs and effects were discounted at a rate of 3.5%. A probabilistic sensitivity analysis was performed.

SETTING

Economic perspective of the Canadian government third-party payer.

PARTICIPANTS

CRS patients with nasal polyposis who have predominantly isolated symptoms of nasal obstruction with or without olfactory loss.

MAIN OUTCOME MEASURES

Incremental cost per quality adjusted life year (QALY).

RESULTS

Over a time period of 30 years, the reference case demonstrated that the ESS strategy cost a total of $21,345 and produced 13.17 QALYs while the EPIC strategy cost a total of $5591 and produced 12.93 QALYs. The ESS versus EPIC incremental cost-effectiveness ratio was $65,641/QALY. The probability that EPIC is cost-effective compared to ESS at a maximum willingness-to-pay threshold of $30,000 and $50,000/QALY is 66% and 60%, respectively.

CONCLUSIONS

Outcomes from this study have demonstrated that the EPIC procedure may be a cost-effective treatment strategy for 'select' patients with nasal polyposis. Data from this study were obtained from a small pilot trial, and we feel the results warrant a future randomised controlled trial to strengthen the outcomes.

Predictors of pursuit of physician-assisted death

CONTEXT

Physician-assisted death (PAD) was legalized in 1997 by Oregon's Death with Dignity Act. The States of Washington, Montana, Vermont, and New Mexico have since provided legal sanction for PAD. Through 2013, 1173 Oregonians have received a prescription under the Death with Dignity Act and 752 have died after taking the prescribed medication in Oregon.

OBJECTIVES

To determine the predictive value of personal and interpersonal variables in the pursuit of PAD.

METHODS

Fifty-five Oregonians who either requested PAD or contacted a PAD advocacy organization were compared with 39 individuals with advanced disease who did not pursue PAD. We compared the two groups on responses to standardized measures of depression, hopelessness, spirituality, social support, and pain. We also compared the two groups on style of attachment to intimate others and caregivers as understood through attachment theory.

RESULTS

We found that PAD requesters had higher levels of depression, hopelessness, and dismissive attachment (attachment to others characterized by independence and self-reliance), and lower levels of spirituality. There were moderate correlations among the variables of spirituality, hopelessness, depression, social support, and dismissive attachment. There was a strong correlation between depression and hopelessness. Low spirituality emerged as the strongest predictor of pursuit of PAD in the regression analysis.

CONCLUSION

Although some factors motivating pursuit of PAD, such as depression, may be ameliorated by medical interventions, other factors, such as style of attachment and sense of spirituality, are long-standing aspects of the individual that should be supported at the end of life. Practitioners must develop respectful awareness and understanding of the interpersonal and spiritual perspectives of their patients to provide such support.

Testing the Transition Preparation Training Program: Well-being of relationships outcomes

PURPOSE

To determine the impact of the availability of everyday relationships and types of social support among adolescents with spina bifida on overall satisfaction/well-being of relationships and whether these adolescents differ in their ratings of relationships, social support and overall satisfaction, as measured by the My Family and Friends Scale: Teenage Version, social support scale after their participation in a health care transition intervention program, entitled the Transition Preparation Training Program.

METHODS

A mixed design ANOVA was conducted. There were 31 eligible adolescents randomly assigned to the treatment group and 34 were assigned to the control group for a total sample size of 65 adolescents (investigator-blinded randomization).

RESULTS

There were significant main effects for support type, relationship type, and for group. The mean overall satisfaction social support ratings for 31 adolescents in the treatment group slightly increased, pre (M = 38.63), post (M = 39.04), while the mean satisfaction social support ratings for those in the control group (34) did not change, pre (M = 39.95), post (M = 39.95).

CONCLUSIONS

Relationship type and social support are important factors in overall satisfaction/well-being of relationships among adolescents with spina bifida. Discussing social networks, when preparing these adolescents for transition, may help promote evaluation of the types of support needed.

Exploration of internet use: profile and preferences of transition-aged adolescents with spina bifida

PURPOSE

A pilot study was conducted to learn about the Internet usage of adolescents with spina bifida. The purpose of this study is to investigate the feasibility for developing an online health care transition intervention.

METHODS

Use of the Internet was examined in a convenience sample of 50 adolescents with spina bifida in the Spina Bifida Clinic at Children's Hospital, Los Angeles. Participants were between 14 to 18 years of age. Data are reported as percentages and frequency distributions.

RESULTS

Ninety-two percent of adolescents with spina bifida used the Internet, and of those, 87% used it at home, with an average rate of 2.4 hours per dat. The majority of adolescents used the Internet for homework purposes (83%). Leisure activities, such as listening to music (76%), playing games (70%), meeting new friends/social networking (63%), and watching YouTube videos (61%), were also reported. Most participants have never used the Internet to obtain spina bifida information (67%) or to meet other adolescents with spina bifida (85%).

CONCLUSION

Internet application as an outreach tool for education and transition planning should be further explored in future studies. Given the widespread reported access to the Internet among our participants, results suggest that a Web-based outreach tool for education and health care transition planning have the potential to be accessible and beneficial to adolescents with spina bifida with the facilitated support of health care professionals.

High-polyphenol chocolate reduces endothelial dysfunction and oxidative stress during acute transient hyperglycaemia in Type 2 diabetes: a pilot randomized controlled trial

AIMS

To investigate the effects of high-polyphenol chocolate upon endothelial function and oxidative stress in Type 2 diabetes mellitus during acute transient hyperglycaemia induced following a 75-g oral glucose challenge.

METHODS

Ten subjects with Type 2 diabetes underwent a double-blinded randomized controlled crossover study. A 75-g oral glucose load was used to induce hyperglycaemia, which was administered to participants 60 min after they had ingested either low (control) or high-polyphenol chocolate. Participants undertook testing at weekly intervals, following an initial cocoa-free period. Endothelial function was assessed by both functional [reactive hyperaemia peripheral artery tonometry (EndoPAT-2000) and serum markers (including intercellular adhesion molecule 1, P-selectin and P-selectin glycoprotein ligand 1]. Urinary 15-F2t-isoprostane adjusted for creatinine was used as an oxidative stress marker. Measurements were made at baseline and 2 h post-ingestion of the glucose load.

RESULTS

Prior consumption of high-polyphenol chocolate before a glucose load improved endothelial function (1.7 ± 0.1 vs. 2.3 ± 0.1%, P = 0.01), whereas prior consumption of control chocolate resulted in a significant increase in intercellular adhesion molecule 1 (321.1 ± 7.6 vs. 373.6 ± 10.5 ng/ml, P = 0.04) and 15-F2t-isoprostane (116.8 ± 5.7 vs. 207.1 ± 5.7 mg/mol, P = 0.02). Analysis of percentage changes from baseline comparing control and high-polyphenol chocolate showed a significant improvement for high-polyphenol chocolate in both measures of endothelial function (P < 0.05) and for urinary 15-F2t-isoprostane (P = 0.04).

CONCLUSION

High-polyphenol chocolate protected against acute hyperglycaemia-induced endothelial dysfunction and oxidative stress in individuals with Type 2 diabetes mellitus.

Short-term glucose variability in healthy volunteers is not associated with raised oxidative stress markers

It is unknown whether glycaemic variability adds to the risk of microvascular complications of diabetes over and above the mean glucose value for a patient. We examined the effect of purposefully induced short-term glycaemic variability on oxidative stress markers. Eleven healthy subjects underwent three sequential glycaemic states; sustained hyperglycaemia, sustained euglycaemia and variable glycaemia, using glycaemic clamps for 3 h. Twenty-four hours urinary 8-isoprostane-PGF2α was measured before and after each glycaemic state to assess oxidative stress. The median and interquartile range of the urinary 8-iso-PGF2α in ng/24 h were (1373, 513), (996, 298) and (1227, 472) for the euglycaemic, hyperglycaemic and variable states, respectively. There was no significant difference in urinary isoprostanes between the three different states; mean ranks 20.9, 11.9 and 18.2 for the euglycaemic state, hyperglycaemic state and glycaemic variability state, respectively, p = 0.083. In conclusion, we did not see a significant increase in the urinary isoprostanes when glycaemic variability was induced under controlled conditions in healthy individuals.

A simplified sum-frequency vibrational imaging setup used for imaging lipid bilayer arrays

Given the complexity of cell membranes, there is a need for an analytical technique which can explore the physical properties of lipid membranes in a high-throughput and noninvasive manner. A simplified sum-frequency vibrational imaging (SFVI) setup has been developed and characterized using asymmetrically prepared 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC):1,2-distearoyl(d70)-sn-glycero-3-phosphocholine (DSPC-d(70)) lipid bilayer arrays. Exploiting the vibrational selectivity and inherent symmetry constraints of sum-frequency generation, SFVI was successfully used to probe the transition temperature of a patterned DSPC:DSPC-d(70) lipid bilayer array. SFVI was also used to study the phase behavior in a multicomponent micropatterned lipid bilayer array (MLBA) prepared using three different binary lipid mixtures (1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC):DSPC, DOPC:1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC:DSPC). This paper demonstrates that a simplified SFVI setup provides the necessary chemical imaging capabilities with the spatial resolution, sensitivity, and field of view required for exploring lipid membrane properties in a high-throughput array based assay.

Thyroid dysfunction and fibrin network structure: a mechanism for increased thrombotic risk in hyperthyroid individuals

CONTEXT

Hyperthyroidism is associated with increased thrombosis risk, and fibrin clot structure determines susceptibility to vascular thrombotic events.

OBJECTIVE

Our objective was to investigate clot formation and lysis in hyperthyroidism using observational and interventional studies.

DESIGN

Ex vivo fibrin clot structure/fibrinolysis and plasma levels of thrombotic/inflammatory markers were investigated in hyperthyroid individuals (n = 24) and matched controls (n = 19), using turbidimetric assays, ELISA, and confocal and electron microscopy. The effects of normalizing thyroid function were analyzed (n = 19) and the role of short-term exogenous hyperthyroidism in healthy volunteers studied (n = 16).

RESULTS

Hyperthyroid subjects displayed higher clot maximum absorbance compared with controls (0.41 ± 0.03 and 0.27 ± 0.01 arbitrary units, respectively; P < 0.01), and longer clot lysis time (518 ± 23 and 461 ± 18 sec, respectively; P < 0.05), which correlated with free T(4) levels. Plasma levels of fibrinogen and plasminogen activator inhibitor-1 were significantly higher in patients compared with controls. Normalizing thyroid function in 19 subjects was associated with lower maximum absorbance and shorter lysis time, accompanied by reduction in fibrinogen, plasminogen activator inhibitor-1, and D-dimer levels. Complement C3, but not C-reactive protein, levels were higher in hyperthyroid subjects compared with controls (0.92 ± 0.05 and 0.64 ± 0.03 g/liter, respectively; P < 0.01), correlated with clot structure parameters, and decreased after intervention. Confocal and electron microscopy confirmed more compact clots and impaired fibrinolysis during hyperthyroidism. Exogenous hyperthyroidism in healthy volunteers had no effect on any of the clot structure parameters.

CONCLUSIONS

Endogenous hyperthyroidism is associated with more compact clots and resistance to fibrinolysis ex vivo, related to the degree of hyperthyroidism and C3 plasma levels, and these changes are modulated by achieving euthyroidism. Altered clot structure/lysis may be one mechanism for increased thrombotic risk in hyperthyroidism.

A novel mechanism for hypofibrinolysis in diabetes: the role of complement C3

AIMS/HYPOTHESIS

Impaired fibrin clot lysis is a key abnormality in diabetes and complement C3 is one protein identified in blood clots. This work investigates the mechanistic pathways linking C3 and hypofibrinolysis in diabetes using ex vivo/in vitro studies.

METHODS

Fibrinolysis and C3 plasma levels were determined in type 1 diabetic patients and healthy controls, and the effects of glycaemia investigated. C3 incorporation into fibrin clots and modulation of fibrinolysis were analysed by ELISA, immunoblotting, turbidimetric assays and electron and confocal microscopy.

RESULTS

Clot lysis time was longer in diabetic children than in controls (599 ± 18 and 516 ± 12 s respectively; p < 0.01), C3 levels were higher in diabetic children (0.55 ± 0.02 and 0.43 ± 0.02 g/l respectively; p < 0.01) and both were affected by improving glycaemia. An interaction between C3 and fibrin was confirmed by the presence of lower protein levels in sera compared with corresponding plasma and C3 detection in plasma clots by immunoblot. In a purified system, C3 was associated with thinner fibrin fibres and more prolongation of lysis time of clots made from fibrinogen from diabetic participants compared with controls (244 ± 64 and 92 ± 23 s respectively; p < 0.05). Confocal microscopy showed higher C3 incorporation into diabetic clots compared with controls, and fully formed clot lysis was prolonged by 764 ± 76 and 428 ± 105 s respectively (p < 0.05). Differences in lysis, comparing diabetes and controls, were not related to altered plasmin generation or C3-fibrinogen binding assessed by plasmon resonance.

CONCLUSIONS/INTERPRETATION

C3 incorporation into clots from diabetic fibrinogen is enhanced and adversely affects fibrinolysis. This may be one novel mechanism for compromised clot lysis in diabetes, potentially offering a new therapeutic target.

Correlations between perfusion MR imaging cerebral blood volume, microvessel quantification, and clinical outcome using stereotactic analysis in recurrent high-grade glioma

BACKGROUND AND PURPOSE

Quantifying MVA rather than MVD provides better correlation with survival in HGG. This is attributed to a specific "glomeruloid" vascular pattern, which is better characterized by vessel area than number. Despite its prognostic value, MVA quantification is laborious and clinically impractical. The DSC-MR imaging measure of rCBV offers the advantages of speed and convenience to overcome these limitations; however, clinical use of this technique depends on establishing accurate correlations between rCBV, MVA, and MVD, particularly in the setting of heterogeneous vascular size inherent to human HGG.

MATERIALS AND METHODS

We obtained preoperative 3T DSC-MR imaging in patients with HGG before stereotactic surgery. We histologically quantified MVA, MVD, and vascular size heterogeneity from CD34-stained 10-μm sections of stereotactic biopsies, and we coregistered biopsy locations with localized rCBV measurements. We statistically correlated rCBV, MVA, and MVD under conditions of high and low vascular-size heterogeneity and among tumor grades. We correlated all parameters with OS by using Cox regression.

RESULTS

We analyzed 38 biopsies from 24 subjects. rCBV correlated strongly with MVA (r = 0.83, P < .0001) but weakly with MVD (r = 0.32, P = .05), due to microvessel size heterogeneity. Among samples with more homogeneous vessel size, rCBV correlation with MVD improved (r = 0.56, P = .01). OS correlated with both rCBV (P = .02) and MVA (P = .01) but not with MVD (P = .17).

CONCLUSIONS

rCBV provides a reliable estimation of tumor MVA as a biomarker of glioma outcome. rCBV poorly estimates MVD in the presence of vessel size heterogeneity inherent to human HGG.

Solid State Multinuclear Magnetic Resonance Investigation of Electrolyte Decomposition Products on Lithium Ion Electrodes

Solid electrolyte interphase (SEI) formation in lithium ion cells prepared with advanced electrolytes is investigated by solid state multinuclear (⁷Li, ¹⁹F, ³¹P) magnetic resonance (NMR) measurements of electrode materials harvested from cycled cells subjected to an accelerated aging protocol. The electrolyte composition is varied to include the addition of fluorinated carbonates and triphenyl phosphate (TPP, a flame retardant). In addition to species associated with LiPF₆ decomposition, cathode NMR spectra are characterized by the presence of compounds originating from the TPP additive. Substantial amounts of LiF are observed in the anodes as well as compounds originating from the fluorinated carbonates.

Using micropatterned lipid bilayer arrays to measure the effect of membrane composition on merocyanine 540 binding

The lipophilic dye merocyanine 540 (MC540) was used to model small molecule-membrane interactions using micropatterned lipid bilayer arrays (MLBAs) prepared using a 3D Continuous Flow Microspotter (CFM). Fluorescence microscopy was used to monitor MC540 binding to fifteen different bilayer compositions simultaneously. MC540 fluorescence was two times greater for bilayers composed of liquid-crystalline (l.c.) phase lipids (1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC),1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine (SOPC), and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)) compared to bilayers in the gel phase (1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)). The effect cholesterol (CHO) had on MC540 binding to the membrane was found to be dependent on the lipid component; cholesterol decreased MC540 binding in DMPC, DPPC and DSPC bilayers while having little to no effect on the remaining l.c. phase lipids. MC540 fluorescence was also lowered when 1,2-dioleoyl-sn-glycero-3-phospho-L-serine (sodium salt) (DOPS) was incorporated into DOPC bilayers. The increase in the surface charge density appears to decrease the occurrence of highly fluorescent monomers and increase the formation of weakly fluorescent dimers via electrostatic repulsion. This paper demonstrates that MLBAs are a useful tool for preparing high density reproducible bilayer arrays to study small molecule-membrane interactions in a high-throughput manner.

A comparison of methods for the measurement of 8-isoPGF(2α): a marker of oxidative stress

BACKGROUND

Oxidative stress describes the cellular damage caused by excess reactive oxygen species not adequately inactivated by antioxidants. Oxidative stress has been implicated in playing a role in many disorders. Lipid peroxidation end-products are employed as markers of oxidative stress, of which the isoprostane, 8-iso-PGF(2α), is widely used. 8-iso-PGF(2α) is measured in plasma or urine by gas chromatography-mass spectrometry (GC/MS), liquid chromatography-mass spectrometry (LC/MS), tandem-mass spectrometry or enzyme-linked immunosorbent assay (ELISA). However, discrepancies between the specificity of these methods means correlation is poor.

METHODS

A tandem-mass spectrometric (LC/MS/MS) method, using immunoaffinity purification, for urinary 8-iso-PGF(2α) was developed and compared with two commercial ELISAs (A--Cayman Chemicals, B--Oxford Biomedical Research) in urine samples (n = 156).

RESULTS

An LC/MS/MS method coupled to immunoaffinity purification was developed with satisfactory performance and comparison to ELISAs A and B. Spearman rank correlation demonstrated significant correlation between all methods (P = <0.0001); however, r² values ranged from 0.68 to 0.72. Bland-Altman plots revealed a proportional positive bias of ELISA B when compared with ELISA A and LC/MS/MS. Furthermore, the agreement between ELISA A and LC/MS/MS was poor.

CONCLUSIONS

The poor agreement between methods for measurement of 8-iso-PGF(2α) highlights differences in selectivity. 8-iso-PGF(2α) is an isoprostane, a family of isomeric end-products of arachidonic acid peroxidation, which are produced by peroxidation or enzymatically. This makes avoiding cross-reactivity between 8-iso-PGF(2α) and related isomers challenging. When assessing oxidative stress studies, the selectivity of the methods used should be taken into account, particularly when comparing studies.

Multivalent immunity targeting tumor-associated antigens by intra-lymph node DNA-prime, peptide-boost vaccination

Active immunotherapy of cancer has yet to yield effective therapies in the clinic. To evaluate the translatability of DNA-based vaccines we analyzed the profile of T-cell immunity by plasmid vaccination in a murine model, using transcriptome microarray analysis and flow cytometry. DNA vaccination resulted in specific T cells expressing low levels of co-inhibitory molecules (most notably PD-1), strikingly different from the expression profile elicited by peptide immunization. In addition, the T-cell response primed through this dual-antigen-expressing plasmid (MART-1/Melan-A and tyrosinase) translated into a substantial proliferation capacity and functional conversion to antitumor effector cells after tyrosinase and MART-1/Melan-A peptide analog boost. Furthermore, peptide boost rescued the immune response against the subdominant tyrosinase epitope. This immunization approach could be adapted to elicit potent immunity against multiple tumor antigens, resulting in a broader immune response that was more effective in targeting human tumor cells. Finally, this study sheds light on a novel mechanism of immune homeostasis through synchronous regulation of co-inhibitory molecules on T cells, highly relevant to heterologous prime boost approaches involving DNA vaccines as priming agents.

High-resolution solid-state NMR of quadrupolar nuclei

We report the observation of high-resolution solid-state NMR spectra of (23)Na (I = [unk]), (27)Al (I = [unk]) and (51)V (I = [unk]) in various inorganic systems. We show that, contrary to popular belief, relatively high-resolution ( approximately 10 ppm linewidth) spectra may be obtained from quadrupolar systems, in which electric quadrupole coupling constants (e(2)qQ/h) are in the range approximately 1-5 MHz, by means of observation of the ((1/2), -(1/2)) spin transition. The ((1/2), -(1/2)) transition for all nonintegral spin quadrupolar nuclei (I = [unk], [unk], [unk], or [unk]) is only normally broadened by dipolar, chemical shift (or Knight shift) anisotropy or second-order quadrupolar effects, all of which are to a greater or lesser extent averaged under fast magic-angle sample rotation. In the case of (23)Na and (27)Al, high-resolution spectra of (23)NaNO(3) (e(2)qQ/h approximately 300 kHz) and alpha-(27)Al(2)O(3) (e(2)qQ/h approximately 2-3 MHz) are presented; in the case of (51)V(2)O(5) (e(2)qQ/h approximately 800 kHz), rotational echo decays are observed due to the presence of a approximately 10(3)-ppm chemical shift anisotropy. The observation of high-resolution solid-state spectra of systems having spins I = [unk], [unk], and [unk] in asymmetric environments opens up the possibility of examining about two out of three nuclei by solid-state NMR that were previously thought of as "inaccessible" due to the presence of large (a few megahertz) quadrupole coupling constants. Preliminary results for an I = [unk] system, (93)Nb, having e(2)qQ/h approximately 19.5 MHz, are also reported.

A unified framework for chaotic neural-network approaches to combinatorial optimization

As an attempt to provide an organized way to study the chaotic structures and their effects in solving combinatorial optimization with chaotic neural networks (CNN's), a unifying framework is proposed to serve as a basis where the existing CNN models can be placed and compared. The key of this proposed framework is the introduction of an extra energy term into the computational energy of the Hopfield model, which takes on different forms for different CNN models, and modifies the original Hopfield energy landscape in various manners. Three CNN models, namely the Chen and Aihara model with self-feedback chaotic simulated annealing (CSA), the Wang and Smith model with timestep CSA, and the chaotic noise model, are chosen as examples to show how they can be classified and compared within the proposed framework.

Optimized preload leakage-correction methods to improve the diagnostic accuracy of dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in posttreatment gliomas

BACKGROUND AND PURPOSE

Relative cerebral blood volume (rCBV) accuracy can vary substantially depending on the dynamic susceptibility-weighted contrast-enhanced (DSC) acquisition and postprocessing methods, due to blood-brain barrier disruption and resulting T1-weighted leakage and T2- and/or T2*-weighted imaging (T2/T2*WI) residual effects. We set out to determine optimal DSC conditions that address these errors and maximize rCBV accuracy in differentiating posttreatment radiation effect (PTRE) and tumor.

MATERIALS AND METHODS

We recruited patients with previously treated high-grade gliomas undergoing image-guided re-resection of recurrent contrast-enhancing MR imaging lesions. Thirty-six surgical tissue samples were collected from 11 subjects. Preoperative 3T DSC used 6 sequential evenly timed acquisitions, each by using a 0.05-mmol/kg gadodiamide bolus. Preload dosing (PLD) and baseline subtraction (BLS) techniques corrected T1-weighted leakage and T2/T2*WI residual effects, respectively. PLD amount and incubation time increased with each sequential acquisition. Corresponding tissue specimen stereotactic locations were coregistered to DSC to measure localized rCBV under varying PLD amounts, incubation times, and the presence of BLS. rCBV thresholds were determined to maximize test accuracy (average of sensitivity and specificity) in distinguishing tumor (n = 21) and PTRE (n = 15) samples under the varying conditions. Receiver operator characteristic (ROC) areas under the curve (AUCs) were statistically compared.

RESULTS

The protocol that combined PLD (0.1-mmol/kg amount, 6-minute incubation time) and BLS correction methods maximized test AUC (0.99) and accuracy (95.2%) compared with uncorrected rCBV AUC (0.85) and accuracy (81.0%) measured without PLD and BLS (P = .01).

CONCLUSIONS

Combining PLD and BLS correction methods for T1-weighted and T2/T2*WI errors, respectively, enables highly accurate differentiation of PTRE and tumor growth.

Meningococcal disease in a backpackers hostel in Scotland: a risk assessment for prophylaxis

This paper outlines the risk assessment and communication strategy carried out by the Lothian Health Protection Team after notification of a probable case of meningococcal disease (later confirmed as Neisseria meningitidis) in a resident of a city centre backpackers hostel. Six close contacts were identified from the hostel and given rifampicin prophylaxis. Two days after commencing rifampicin one of these contacts was admitted to hospital with a purpuric/petechial rash and thrombocytopenia. The final diagnosis for this contact was thrombocytopenia, either idiopathic or secondary to rifampicin. This example and the potential side effects of administering rifampicin prophylaxis highlight the importance of a thorough risk assessment of contacts of a case to avoid prescribing prophylaxis to anyone other than those at highest risk of becoming a subsequent case.